Refrigerated merchandiser

ABSTRACT

A refrigerated merchandiser has a cabinet defining an interior product display space. A generally vertically extending air supply duct at the rear of the cabinet has an inlet for receiving the refrigerated air and an outlet at its upper end for passing the refrigerated air from the air supply duct into an upper region of the interior space along the top wall of cabinet. An evaporator fan in a compartment beneath the interior space draws air flow downwardly through the product display space and through a return air inlet in the lower wall separating the compartment from the interior space. A flow baffle may be disposed in the upper region of the interior space for directing the air downwardly into the interior space to pass through the product displayed therein and out the air return outlet in the lower wall.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser. No. 60/663,472, filed Mar. 18, 2005, and entitled COLD AIR DISTRIBUTION DUCT FOR BOTTLE COOLER, which application is incorporated herein in its entirety by reference.

This application is related to the following applications subject to assignment to the common assignee of this application and filed with the United States Patent and Trademark Office on the same date as this application:

-   U.S. patent application Ser. No. (Attorney Docket No. 210_(—)816NP),     entitled “SEALING SYSTEM FOR REFRIGERATION CASSETTE”; -   U.S. patent application Ser. No. (Attorney Docket No. 210_(—)820NP),     entitled “MODULAR REFRIGERATION CASSETTE”; -   U.S. patent application Ser. No. (Attorney Docket No. 210_(—)879NP),     entitled “MODULAR REFRIGERATION CASSETTE WITH CONDENSATE EVAPORATIVE     TRAY”; -   U.S. patent application Ser. No. (Attorney Docket No. 210_(—)818NP),     entitled “BOTTOM DECK ASSEMBLY FOR REFRIGERATED MERCHANDISER”; and -   U.S. patent application Ser. No. (Attorney Docket No. 210_(—)819NP),     entitled “EVAPORATOR FAN/MOTOR ASSEMBLY MOUNTING BRACKET”.     Each of the afore-listed patent applications is incorporated herein     by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to display cabinets in general and, more particularly, to refrigerated cabinets equipped with modular cassette refrigeration units.

BACKGROUND OF THE INVENTION

Refrigerated cabinets have a refrigeration system associated therewith for providing the cooled environment within the interior of the refrigerated cabinet. The refrigeration systems of such refrigerated cabinets commonly employ a conventional refrigeration cycle and include an evaporator and an evaporator fan operatively associated with the interior of the refrigerated cabinet, as well as a condenser, a condenser fan, and compressor. In stand alone cabinets, the compressor, condenser and condenser fan are housed in an equipment compartment separate from and insulated from the cooled interior of the refrigerated cabinet. A refrigerant is circulated by a compressor through refrigerant lines connecting the compressor, the condenser and the evaporator in a conventional manner to form a closed circuit. Air within the insulated interior of the refrigerated cabinet is circulated by the evaporator fan through the evaporator in heat exchange relationship with the refrigerant so as to cool the air. The evaporator and evaporator fan may be disposed within the cooled interior of the refrigerated cabinet, for example in the upper region thereof.

However, the evaporator and evaporator fan may also be housed in the equipment compartment in a section of the equipment compartment insulated from the compressor, condenser and condenser fan. Among other uses, refrigerated cabinets of this type may be used as refrigerator or freezer display case merchandisers, vending machines, and cold beverage merchandisers in supermarkets, grocery stores, gas stations, convenience stores, and other retail establishments. For example, cold beverages, such as soft drinks, beer, wine coolers, etc. are commonly displayed in refrigerated merchandisers for self-service purchase by customers. Conventional beverage merchandisers of this type include an insulated cabinet defining a refrigerated product display zone having one or more glass doors that provide access to the refrigerated interior. The beverage product, typically in cans or bottles, single or in multi-packs, is stored on shelves within the refrigerated display zone of the cabinet. To purchase a beverage, the customer opens one of the doors and reaches into the refrigerated cabinet to retrieve the desired product from the shelf.

Refrigerated merchandisers equipped with modular cassette refrigeration units disposed atop the refrigerated cabinet are disclosed, for example, by Bauman et al. in U.S. Pat. Nos. 5,953,929 and 6,070,424, and by Morse in U.S. Pat. No. 6,701,739. Refrigerated merchandisers equipped with modular cassette refrigeration units disposed beneath the refrigerated cabinet are disclosed, for example, by Rudick et al. in U.S. Pat. Nos. 5,347,827; 5,402,654; 5,417,079; and 5,417,081 and by Maynard et al. in U.S. Pat. No. 5,678,421.

In refrigerated merchandisers equipped with modular cassette refrigeration units disposed beneath the refrigerated cabinet, the refrigerated air from the refrigeration unit follows a generally circular circulation pattern within the product display zone of the cabinet. The refrigerated air typically flows from the refrigeration unit up along the back wall of the cabinet, to the top wall of the cabinet, thence along the top wall of the cabinet, and thence down the front of the cabinet to the floor of the product display zone and through an air return inlet to the refrigeration unit. However, with a generally circular circulation pattern, a uniformly even product temperature distribution may not be achieved as product disposed centrally within the product display zone or on the side and rear portions of the lower shelves may not be sufficiently contacted by the circulating refrigeration air. Additionally, as the refrigerated air passing along the top wall of the cabinet has a high horizontal velocity component, a significant amount of cold refrigerated air impinges on the inner surface of the door of the merchandiser and travels down the front of the door. This cold air passing down the front of the door may cause excessive condensation on the colder door surfaces.

SUMMARY OF THE INVENTION

It is an object of one aspect of the invention to provide a refrigerated merchandiser having a refrigerated air flow passing generally vertically downward through the product displayed therein.

It is an object of another aspect of the invention to provide a method for circulating refrigerated air in a refrigerated merchandiser providing a generally vertically downwardly directed flow through at least a central portion of product displayed therein.

It is an object of one aspect of the invention to provide an improved distribution of refrigerated air to the product display space of a refrigerated merchandiser to reduce product cool down time and to reduce variation in product temperature within the product display space.

It is an object of one aspect of the invention to provide an improved distribution of refrigerated air to the product display space of a refrigerated merchandiser to reduce the flow of cold refrigerated air down the front glass door of the refrigerated merchandiser.

In one aspect of the invention, a refrigerated merchandiser is provided having a cabinet having an interior space wherein a product may be displayed in an environment refrigerated by refrigerated air supplied to the interior space. The cabinet has a top wall, a lower wall having an air return outlet passing therethrough, a rear wall, and side walls bounding the interior space. A rear panel is disposed in the interior space in spaced relationship from and generally parallel to the rear wall of said cabinet, thereby defining a generally vertically extending air supply duct therebetween. The air supply duct has an inlet for receiving the refrigerated air and an outlet at its upper end for passing the refrigerated air from the air supply duct into an upper region of the interior space along the top wall of cabinet. One or more flow baffles may be disposed in the upper region of the interior space for redirecting the air flow passing along the top wall of cabinet downwardly into the interior space to pass through the product displayed therein and out the air return outlet in the lower wall.

In one embodiment, the flow area at the outlet of the supply duct is less than the flow area of the supply duct upstream of the outlet. The flow area may be reduced by a flow restriction, such as for example, a flow baffle disposed at the outlet of the air supply duct so as to restrict the outlet flow area to a flow area less than the flow area in the upstream portion of the supply duct. The flow baffle may be an extension of the rear panel extending obliquely at an upper end of said rear panel toward the rear wall of the cabinet.

In another aspect of the invention, a top panel is disposed in the interior space in spaced relationship from and generally parallel to the top wall of the cabinet, thereby defining a generally horizontally extending air distribution duct therebetween. The top panel has a first plurality of openings therethrough in a rearward portion of the panel and has a second plurality of openings therethrough in a forward portion of the panel. The air distribution duct has an inlet opening in flow communication with the outlet of the air supply duct. In this embodiment, a flow baffle is provided in the air distribution duct intermediate the first plurality of openings in the top panel and the second plurality of openings in the top panel. The flow baffle causes air in the air distribution duct flowing past the baffle to reverse flow direction, whereby a portion of the refrigerated air flowing into the interior space from the air distribution duct enters the interior space through the first plurality of openings in a generally downwardly and forwardly direction. Therefore, a portion of the refrigerated air flowing into the interior space from the air distribution duct enters the interior space through the first plurality of openings in a generally downwardly and rearwardly direction.

In a further aspect of the invention, the rear panel may have a plurality of openings therethrough for passing a portion of the refrigerated air from the air supply duct into the lower and/or central regions of interior space. In an embodiment, a plurality of relatively larger openings are provided in a portion of the rear panel bounding a lower region of the interior space, no openings are provided in a portion of the rear panel bounding an upper region of the interior space, and a plurality of relatively smaller openings are provided in a portion of the rear panel bounding an central portion of the interior space.

A refrigeration unit may be provided in operative association with and exteriorly of the interior space. The refrigeration unit includes an evaporator and an evaporator fan disposed in operative association with the evaporator. The evaporator fan operative to draw air from the interior space through the air return opening in the lower wall to the evaporator of said refrigeration unit and pass refrigerated air from refrigeration unit into said air supply duct. The unit may be disposed in an equipment compartment beneath the lower wall with the air return outlet in the lower wall being in air flow communication with the evaporator fan. The refrigeration unit may include a refrigeration unit cassette having a first compartment housing the evaporator and evaporator fan assembly and a second compartment housing a condenser, a condenser fan assembly in operative association with the condenser, and a compressor, with the evaporator, compressor and condenser coupled in refrigerant flow communication in a closed loop refrigeration circuit. The first compartment of the refrigeration unit cassette has an air inlet in air flow communication with the air return outlet in the lower wall and an air outlet in air flow communication with the air inlet to the air supply duct. The cassette refrigeration unit may be selectively positionable into and out of the equipment compartment.

In another aspect of the invention, a method is provided for refrigerating product displayed within an interior space of refrigerated merchandiser refrigerated by supplying refrigerated air to the interior space. The method includes the steps of: supplying refrigerated air to an upper region of the interior space, directing the refrigerated air supplied to the upper region of the interior space generally vertically downwardly through the product displayed in the interior space, and withdrawing air from a lower region of the interior space. Directing the refrigerated air supplied to the upper region of the interior space generally vertically downwardly through the product displayed in the interior space may include directing a first portion of the refrigerated air supplied to the upper region of the interior space in a generally downwardly and forwardly direction, and directing a second portion of the refrigerated air supplied to the upper region of the interior space in a generally downwardly and rearwardly direction in opposition to the first portion of air.

BRIEF DESCRIPTION OF THE DRAWINGS

For a further understanding of these and objects of the invention, reference will be made to the following detailed description of the invention which is to be read in connection with the accompanying drawing, where:

FIG. 1 is a sectioned side elevation view of one embodiment of a refrigerated merchandiser in accord with the invention;

FIG. 2 is a sectioned side elevation view of another embodiment of a refrigerated merchandiser in accord with the invention;

FIG. 3 is an elevation view, partly in section, taken along line 3-3 of FIG. 1;

FIG. 4 is an elevation view, partly in section, taken along line 4-4 of FIG. 2; and

FIG. 5A-5D are exploded views of respective exemplary embodiments in accord with the invention of an air distribution duct in the upper region the product display space of the refrigerated merchandiser of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 and 2, there is depicted, in alternate embodiments, a refrigerated cold beverage merchandiser, designated generally by the reference numeral 10, including an interior product display space 100 for holding product 110 to be purchased, such as for example bottled or canned soda, milk, water, juices, fruit drinks, beer and other beverages. Although the invention will be described herein with reference to the depicted embodiments of a refrigerated cold beverage merchandiser, it is to be understood that that invention may be applied to other refrigerated display merchandisers for displaying perishable and frozen comestibles and beverages, including for example meats, poultry, fish, diary products, prepackaged frozen foods, and other products that need to be maintained in a controlled environment.

The beverage merchandiser 10 includes a cabinet 20 defining a refrigerated interior product display space 100 and a separate equipment compartment 55 disposed separate from, and may be heat transfer insulated from, the refrigerated interior product display space 100. The cabinet 20 has a top wall 22 and a surrounding side wall structure including a rear wall 34, a front wall 32, and opposed generally vertically extending side walls 36 and 38. The cabinet also includes a lower wall 24 disposed between the refrigerated interior product display space 100 located thereabove and the equipment compartment 55 located there beneath. The interior product display space 100 may be accessed from exteriorly of the cabinet 20 through an access opening, which in the depicted embodiment is an open area at the front of the cabinet. This open area may be open to the environment or may be covered, as in the depicted embodiment, by at least one door 40 mounted to the cabinet 20. The door 40 extends across the open area and has a transparent viewing area, for example a glass panel, through which at least a portion of the interior product display space 100 can be viewed. The door 40 is selectively positionable between a closed position covering the open area and an open position in which consumers may access the interior product display space 100 to remove a product for purchase. Although the embodiment of the display merchandiser 10 depicted in the drawing has only one door 40, it is to be understood that the display merchandiser may have one, two, three or more doors that collectively cover the open area when in the closed position. The door or doors 40 may be mounted to the cabinet 20 in a conventional manner, for example on hinges for pivotal movement or on a track for sliding movement between an open and closed position.

The top wall 22, the lower wall 24, rear wall 34 and the side walls 36 and 38 may be heat transfer insulated for insulating the refrigerated interior space from the environment exterior of the display merchandiser 10. A plurality of shelves 112, including an upper shelf 112A and a lower shelf 112B, are disposed within the product display space 100. The shelves 112 are adapted as appropriate to support the particular product 110 being displayed for purchase. The specific number, arrangement and configuration of the shelves 112 is not germane to the invention and is within the skill of one of ordinary skill in the art to select for the particular product 100 being displayed.

A rear panel 134 is provided spaced inwardly of the rear side wall 34 to establish an air supply duct 104 between the rear side wall 34 and a rear panel 134. In the embodiment depicted in FIG. 1, the product display space 100 is bounded by the top wall 22, rear panel 134, the lower wall 24 and the side walls 36 and 38. Air enters into the refrigerated product display space 100 to cool product displayed therein in part through an air outlet 109 at the upper end of the air supply duct 104 and in part through a plurality of openings 135 provided in the rear panel 134. In the embodiment depicted in FIG. 2, a top panel 122 is provided spaced inwardly of the top wall 22 to establish a generally horizontally extending air duct 106 between the top wall 22 and a top panel 122. In this embodiment, the product display space 100 is bounded by the top panel 122, rear panel 134, the lower wall 24 and the side walls 36 and 38. A portion of the refrigerated air passing through the air supply duct 104 passes into the interior product display space 100 through openings 135 provided in the rear panel 134 and a portion of the refrigerated air passes from supply duct 104 into duct 106 to passes through openings 123 and 125 provided in the top panel 122.

The equipment compartment 55 is located within the cabinet 20 beneath the lower wall 24 and is separated by the lower wall 24 from the refrigerated interior product display space 100 of the cabinet 20. The lower wall 24 forms a common wall separating the refrigerated interior space and the equipment compartment. The lower wall has a top surface that forms the floor or deck of the interior product display space 100 and has an under surface that faces the refrigeration cassette 50 housed within the equipment compartment. The refrigeration unit 15 includes an evaporator 60 and at least one associated evaporator fan/motor assembly 62, a condenser 70 and at least one associated condenser fan/motor assembly 72, and a compressor 74. The evaporator 60 and its associated evaporator fan/motor assembly 62 are housed within a first section 53 of the refrigeration unit 15 which is separated by division wall 68 from a second section 57 of the refrigeration unit 50 wherein the condenser 70, its associated condenser fan/motor assembly 72 and the compressor 74 are housed.

The refrigeration unit 15 incorporates a cassette 50 having a generally rectangular box-like structure having a top flange 52, a base plate 54, and a surrounding structure extending generally vertically between the top flange 52 and the base plate 54 formed of a back plate 56B, a front plate 58A, and opposed side plates 56C. The division wall 68 extends between the opposed side plates 56C from a forward region of the refrigeration cassette to the back plate 56B to separate the interior of the refrigeration unit cassette 50 into the aforementioned first section 53 and second section 57. The condenser 70, its associated condenser fan/motor assembly 72, and the compressor 74 are mounted to a common support plate that is adapted to be mounted to the base plate 54 which forms the floor of the cassette refrigeration unit 50. The base plate 54 may be slidably mounted within the compartment 55 to facilitate disposition into and out of the compartment 55 in order to facilitate servicing of the refrigeration equipment mounted thereon. A condensate tray 76 may be provided beneath the evaporator 60 to collect condensate dripping from the condenser 70 and the evaporator 60 and draining the collected condensate to a waste line. The condensate tray 76 serves as a condensate evaporative tray wherein condensate collecting therein is evaporated by hot air exhausted from the condenser as the hot air passes over the condensate tray 76.

The evaporator 60, the condenser 70 and the compressor 74 are coupled in a closed-loop refrigerant circulation circuit (not shown) in a conventional manner for refrigerating air from the interior product display space 100. The condenser fan/motor assembly 72, typically a single fan and motor, is operative, typically only when the compressor 74 is in operation, to draw air from outside the refrigerated merchandiser 10, such as for example from the ambient environment external thereof through the front grille 12 provided in the lower front of the merchandiser 10, and through an opening 59I the front plate 58 to the condenser 70. As the external air passes through the condenser 70 in heat exchange relationship with the refrigerant being passed therethrough by the compressor 74, the refrigerant is cooled and the air heated. Having traversed the condenser 70, this air is exhausted out of the compartment 55 through an opening at the rear of the cabinet to return to the external environment. A portion of the air drawn through the refrigeration unit cassette 50 by the condenser fan 72 passes over the compressor 74 to assist in cooling the compressor.

The cooled refrigerant passes from the condenser 70 through the closed-loop refrigerant circulation circuit (not shown) to the evaporator 60. An evaporator fan/motor assembly 62 or a plurality of evaporator fan/motor assemblies 62 operate to draw air into the first section 53 of the refrigeration unit 50, also referred to as the evaporator compartment, from the interior product display space 100 through air inlet 102 in the lower wall 24 and thence pass the air through the evaporator 60 to and through the refrigerated air supply duct to return to the product display space 100. As the circulating air passes through the evaporator 60, the air is cooled as it passes in heat exchange relationship with the chilled refrigerant passed through the evaporator 60 by the compressor 74 and the refrigerant is heated and evaporated. The evaporator fan 62 circulates refrigerated air having traversed the evaporator 60 from the evaporator compartment 53 back into the refrigerated interior product display space 100 through a return air outlet 108 located in the aft portion of the lower wall 24 at the rear of the compartment and opening into refrigerated air supply duct 104.

A cover plate 120 may be disposed over the return air inlet 102 in spaced relationship with and super adjacent the lower wall 24 thereby forming flow passage between the cover plate 120 and the lower wall 24 through which refrigerated air returning from the product display space 100 flows into the return air inlet 102. The cover plate 120 covers the return air inlet 102, thereby preventing spills or leaks from product in the product display space 100 from flowing into the evaporator compartment 53 and fouling the evaporator and/or evaporator fan assembly. Further, the cover plate 120 causes the downwardly directed refrigerated air to flow outwardly toward the surrounding walls of the cabinet as the refrigerated air approaches the lower region of the product display space 100 in order to pass beneath the cover plate 120 into the air inlet 102 in the lower wall 24. In doing so, the refrigerated air passes through the product on the lower shelves to more evenly cool that product and to block the refrigerated air from funneling downwardly directly into the return air inlet 102.

In one embodiment, the cover plate 120 includes a circumferential flange 126 extending generally vertically downwardly therefrom to the base wall 24 for supporting the cover plate 120 over the air inlet 102 in the base wall 124. A plurality of circumferentially spaced openings 125 are provided in the circumferential flange 126 to form the air flow passage connecting the refrigerated interior product display space 100 in flow communication with the air inlet 102 to the evaporator compartment 53 of the refrigeration unit cassette 50.

A sealing member 58 is positioned between the lower wall 24 and the refrigeration unit cassette 50 and a lifting apparatus 150 for placing the refrigeration unit cassette 50 into sealing relationship with the lower wall 24, which separates the refrigerated interior product display space 100 from the equipment compartment 55.

Sealing member 58 may be mounted to the under surface of the lower wall 24 about the opening 102 in the lower wall 24, or may be mounted or simply carried, as illustrated, upon to the upper surface of the top flange 52 of the refrigeration unit cassette 50. The sealing member 58 extends at least about the opening 51 which is substantially commensurate with the opening 102 in the lower wall 24, and also extends about the opening 108 in the lower wall 24 disposed rearward of the opening 51. The sealing member 58 prevents refrigerated air returning to the refrigeration unit 15 from the product display space 100 from bypassing the evaporator 60 and instead flowing directly into the inlet 108 to the air supply duct 104 from the air return inlet 102. The sealing member 58 also prevents ambient air from externally of the cabinet, such as the ambient air that has been drawn through the front grille 12 to pass through the condenser 70, from being drawn into the refrigerated air returning to the refrigeration unit 15 through the air return inlet 102 in the lower wall 24 and the inlet opening in the top flange 52 of the refrigeration unit cassette 50.

Referring now in particular to the embodiment depicted in FIG. 1, refrigerated air from the evaporator compartment 53 passes through the air outlet 108 into the rear air supply duct 104. The rear air supply duct 104 extends generally vertically upwardly between the rear wall 34 and the rear panel 134 and terminates at its upper end in an air outlet 109. The air outlet 109 opens into the refrigerated interior space at a location above the upper shelve 1 12A, but below the top wall 22. The cross-sectional flow area of the air outlet 109 is restricted, that is less than the cross-sectional flow area of the rear duct 104 upstream with respect to air flow of the outlet 109. For example, a baffle 136 may provided at the outlet end of the air duct 104 so as to extend over the air outlet 109 thereby reducing the cross-section flow area of the air outlet 109 relative to the cross-section flow area of the air duct 104. In the depicted embodiment, the outlet baffle 136 is an extension of the rear panel 134 which extends obliquely at an angle with the vertical rearwardly toward the rear wall 34. The outlet baffle 136 may extend rearwardly at an angle, for example in an angle in the range of 30 to 60 degrees. The outlet baffle 136 may extend rearwardly for a distance sufficient to reduce the cross-sectional flow area at the air outlet 109 to about ¼ to ¾ that of the flow duct 104 upstream of the outlet baffle 136.

In the FIG. 1 embodiment, refrigerated air flowing through the rear duct 104 passes into the interior product display space 100 in part through the air outlet 109 of the rear duct 104 and in part through openings 135 in the rear panel 134. The openings 135 constitute horizontally extending, relatively narrow slots arrayed in a plurality of rows and columns in the rear panel such as, for example, in the exemplary embodiment shown in FIG. 3. The reduction in flow area at the air outlet 109 creates a pressure drop that facilitates air flow distribution into the product display area by causing a desired portion of the air flow entering the flow duct 104 to pass through the openings 135 in the rear panel. The distribution of air flow may be controlled in part by changing the amount of restriction of the flow area at the air outlet 109 to the duct 104, for example by altering the extent to which the outlet baffle 136 restricts the flow area at the air outlet 109. To increase the air flow passing through the air outlet 109 relative to that passing through the openings 135 in the back panel 134, the flow area at the air outlet 109 is increased. Conversely, to decrease the air flow passing through the air outlet 109 relative to that passing through the openings 135 in the back panel 134, the flow area at the air outlet 109 is decreased. The relative reduction in flow area at the air outlet 109 may be selected by altering the configuration, e.g. the length and/or angle, of the outlet baffle 136 accordingly to provide the desired flow area at the air outlet 109.

The air flow entering the interior product display space 100 through the air outlet 109 will flow into the upper portion of the product display space 100 above the upper shelve 11 2A and then be drawn generally vertically by the evaporator fan assembly 62 through the product disposed on the shelves 112 through the return air inlet 102 in the lower wall 24 and into the evaporator compartment 53. One or more flow baffles 140, may be disposed on the upper wall 22 so as to extend downwardly into the interior space 100. The flow baffles 140 extend downwardly into the interior space a relatively short distance, but a distance sufficient to direct air flow passing from the air outlet 109 to turn direction to flow generally vertically downward through the product on the selves 112 in the interior product display space 100. Each flow baffle 140 assists in directing the air flow to pass downwardly through a central region of the interior product display space 100 thereby ensuring more effective cooling of the product of the shelves 112 and minimizing variation in product temperature from the back to the front of the interior product display space 100. If a lamp is disposed across the upper front of the interior product display space 100, a heat shield may be provided in association with the lamp to insulate the product from the heat generated by the lamp and also serve as flow baffle for directing airflow downwardly through the product.

Referring now in particular to the embodiment depicted in FIG. 2, refrigerated air from the evaporator compartment 53 passes through the air outlet 108 into the rear air supply duct 104. The rear air supply duct 104 extends generally vertically upwardly between the rear wall 34 and the rear panel 134 and connects in fluid flow communication with the horizontal supply air duct 106. In this embodiment, refrigerated air passes into the interior product display space 100 in part from the rear duct 104 through openings 135 in the rear panel 134 and in part from upper duct 106 through openings 123 and 125 in the top panel 122. Again, the openings 135 constitute horizontally extending, relatively narrow slots arrayed in a plurality of rows and columns in the rear panel such as, for example, in the exemplary embodiment shown in FIG. 4. In this exemplary embodiment, no openings 135 are provided in the upper portion of the rear panel 134, while the openings 135A provided in the lower region of the rear panel 134 are larger than the openings 135B provided in the central region of the rear panel 134. The collective flow area provided by the openings 135A in the lower portion of the rear panel may be greater than the collective flow area provided by the openings 135B in the central region of the rear panel. Therefore, the distribution of refrigerated air passing through the rear panel 134 from duct 104 into the product display space 100 is vertically skewed from no flow through the upper region of the rear panel, to the greatest portion of flow through the rear panel being through the lower region of the rear panel directly into the lower region of the product display space 100.

Referring again to FIG. 2, the remainder of the refrigerated air passing through the refrigerated air supply duct 104 enters the product display space 100 from the upper duct 106 through openings 123 and 125 passing through the top panel 122. Further exemplary configurations of the upper supply duct 106 are presented in FIGS. 5 a, 5 b, 5 c and 5 d. In each configuration a flow baffle 105 is disposed within the forward portion of the duct 106 and extends from the top panel 122 into and partially across the duct 106 so as to cause the air flowing therethrough beyond the baffle 105 to generally reverse direction at the forward end of the duct 106. Openings 123 are provided in the top panel 122 downstream with respect to air flow of the base of the flow baffle 105, while the openings 125 are provided in the top panel 122 upstream with respect to air flow of the base of the flow baffle 105. Therefore, a first portion of the refrigerated air entering the upper duct 106 from the rear duct 104 will pass through the openings 123 into the product space 100 in a generally downwardly and forwardly direction, while a second portion thereof will pass through the openings 125 into the product display space 100 in a generally downwardly and rearwardly direction. Thus, the refrigerated air entering the product display space 100 through the forward set of openings 125 will have a rearwardly directed horizontal component of velocity which will counter the forwardly directed horizontal component of velocity associated with the refrigerated air entering the product display space 100 through the rearward set of openings 123. The refrigerated air entering the interior product display space 100 from the duct 104 through the openings 123 and 125 in the top panel 122 is drawn generally downwardly through the product 110 disposed on the shelves 112 to the return air inlet 102 in the lower wall 24 and into the evaporator compartment 53 by the evaporator fan assembly 62. Thus, the refrigerated air follows an overall generally vertically downward path through the product 110 disposed on the shelves 112 significantly enhancing the cooling of the product and minimizing variation in product temperature from the back to the front of the product display space 100.

In both depicted embodiments of the invention, a portion of the refrigerated air being supplied through the duct 104 enters the interior product display space 100 through the openings 135 provided in the rear panel 134, and a portion of the refrigerated air passes through the outlet 109 of the duct 104 into the interior product display space 100, either directly as in the FIG. 1 embodiment or through a horizontally disposed extension thereof as in the FIG. 2 embodiment. The overall flow distribution between the two portions may also be altered by increasing or decreasing, as desired, the overall flow area provided by the slots 135 in the rear panel by increasing or decreasing the number of slots 135 or the size of the openings 135. Further, the distribution of that portion of the refrigerated passing through the rear panel may be modified as desired by selectively locating the openings in any desired arrangement, by increasing or decreasing the relative size or relative number of the slots in one part of the rear panel verses the openings another part of the rear panel.

For purposes of illustration, in the exemplary embodiment depicted in FIG. 3, the slots 135 are uniformly sized slots arrayed in three multiple row columns in a vertically central portion of the rear panel only. Each slot has a width of 5.50 inches (139.7 millimeters) and a height of 0.25 inches (6.4 millimeters). In the exemplary embodiment depicted in FIG. 4, the openings 135A and 135B are arrayed in three multiple row columns, with the larger slots 135A, located in the lower region of the panel, having a width of 8.00 inches (203.2 millimeters) and a height of 0.75 inches (19.2 millimeters) and with the smaller slots 135B, located in the vertically middle portion of the panel, having a width of 8.00 inches (203.3 millimeters) and a height of 0.25 inches (6.4 millimeters) It is to be understood that the arrangement, size and number of openings provided in the rear panel 135 is within the design discretion of one skilled in the art. The number of rows and columns selected, the relative distribution and spacing between rows and columns, as well as the particular dimensions of the slots 135, may be varied to provide a desired flow distribution with respect to the refrigerated air that enters the interior product display space 100 through the rear panel 134.

While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims. 

1. A refrigerated merchandiser having an interior space wherein a product may be displayed in an environment refrigerated by refrigerated air supplied to the interior space, comprising: a cabinet having a top wall, a lower wall having an air return outlet passing therethrough, a rear wall, and side walls bounding the interior space; and a rear panel disposed in the interior space in spaced relationship from and generally parallel to the rear wall of said cabinet and defining a generally vertically extending air supply duct therebetween, said air supply duct having an inlet for receiving the refrigerated air and an outlet at its upper end for passing a first portion of the refrigerated air from said air supply duct into an upper region of the interior space; at least one flow baffle disposed in an upper region of the interior space for redirecting air flow in the first portion of refrigerated air passing along the top wall of cabinet downwardly into the interior space to pass through the product displayed therein and out the air return outlet in the lower wall.
 2. A refrigerated merchandiser as recited in claim 1, wherein said at least one flow baffle comprises a flow baffle extending inwardly into the interior space from the top wall.
 3. A refrigerated merchandiser as recited in claim 1, wherein said at least one flow baffle comprises a pair of spaced flow baffles, each flow baffle extending from the top wall inwardly into the interior space.
 4. a refrigerated merchandiser as recited in claim 1, wherein said air supply duct has a first flow area upstream of the outlet thereto and a second flow area at the outlet thereto, the second flow area being less than the first flow area.
 5. A refrigerated merchandiser as recited in claim 4 further comprising a flow restriction disposed at the outlet of said air supply duct, said flow restriction restricting the second flow area to a flow area less than the first flow area.
 6. A refrigerated merchandiser as recited in claim 4 further comprising a flow baffle disposed at the outlet of said air supply duct, said flow baffle restricting the second flow area to a flow area less than the first flow area.
 7. A refrigerated merchandiser as recited in claim 6 wherein said flow baffle comprises an extension of said rear panel extending obliquely at an upper end of said rear panel toward said rear wall of the cabinet.
 8. A refrigerated merchandiser as recited in claim 1 further comprising a plurality of openings in said rear panel for passing a second portion of refrigerated air into the interior space from an upstream portion of said air supply duct.
 9. A refrigerated merchandiser as recited in claim 1 further comprising a refrigeration unit disposed in operative association with and exteriorly of the interior space, said refrigeration unit including an evaporator and an evaporator fan disposed in operative association with the evaporator, the evaporator fan operative to draw air from the interior space through the air return opening in the lower wall to the evaporator of said refrigeration unit and pass refrigerated air from refrigeration unit into said air supply duct.
 10. A refrigerated merchandiser as recited in claim 9 wherein said refrigeration unit is disposed in an equipment compartment beneath the lower wall and the air return outlet in the lower wall is in air flow communication with the evaporator fan.
 11. A refrigerated merchandiser as recited in claim 1 further comprising a refrigeration unit cassette having a first compartment housing an evaporator and an evaporator fan assembly in operative association and a second compartment housing a condenser, a condenser fan assembly in operative association with the condenser, and a compressor, the evaporator, compressor and condenser coupled in refrigerant flow communication in a closed loop refrigeration circuit, the first compartment having an air inlet in air flow communication with the air return outlet in the lower wall and an air outlet in air flow communication with the air inlet to said air supply duct.
 12. A refrigerated merchandiser as recited in claim 11 wherein said cassette refrigeration unit being selectively positionable into and out of the equipment compartment.
 13. A refrigerated merchandiser as recited in claim 1 further comprising a top panel disposed in the interior space in spaced relationship from and generally parallel to the top wall of said cabinet and defining a generally horizontally extending air distribution duct therebetween, said top panel having a first plurality of openings therethrough in a rearward portion thereof and having a second plurality of openings therethrough in a forward portion thereof, said generally horizontally extending air distribution duct having an inlet opening in flow communication with the outlet of said air supply duct.
 14. A refrigerated merchandiser as recited in claim 13 wherein said at least one flow baffle comprises a flow baffle disposed in said air distribution duct intermediate said first plurality of openings in said generally horizontal panel and said second plurality of openings in said generally horizontal panel.
 15. A refrigerated merchandiser as recited in claim 13 wherein said rear panel has a lower portion having a first plurality of openings therethrough, an upper portion without openings therethrough, and an intermediate portion between the upper and lower portions having a second plurality of openings therethrough for passing refrigerated air from said air supply duct into the interior space.
 16. A refrigerated merchandiser as recited in claim 15 wherein said first plurality of openings in the lower portion of said rear panel define a first flow area and said second plurality of openings in the intermediate portion of said rear panel define a second flow area, the first flow area being larger than the second flow area.
 17. A refrigerated merchandiser having an interior space housing a product in a refrigerated environment intended for selection by consumers, comprising: a cabinet having a top wall, a lower wall, a rear wall, and side walls defining the interior space, said lower wall having an air return opening therethrough; a generally vertical panel disposed in the interior space spaced from and generally parallel to the rear wall of said cabinet and defining a refrigerated air supply duct therebetween; a generally horizontal panel disposed in the interior space in spaced relationship from and generally parallel to the top wall of said cabinet and defining a first air duct therebetween, said generally horizontal panel having a rearward portion and a forward portion, said first and second air ducts being in flow communication thereby establishing a refrigerated air distribution duct; a first plurality of openings disposed in and through the rearward portion of said generally horizontal panel for passing refrigerated air from said air distribution duct into the interior product display space in a generally downwardly and forwardly direction; a second plurality of openings disposed in and through the forward portion of said generally horizontal panel for passing refrigerated air from said air distribution duct into the interior product display space in a generally downwardly and rearwardly direction; and a refrigeration unit disposed beneath the lower wall in operative association with the interior space, said refrigeration unit including an evaporator and an evaporator fan disposed in operative association with the evaporator, the evaporator fan operative to draw air from the interior space through the air return opening in the lower wall to the evaporator of said refrigeration unit and pass refrigerated air from refrigeration unit into said air supply duct.
 18. A refrigerated merchandiser as recited in claim 17 further comprising: a flow baffle disposed said air distribution duct intermediate the first plurality of openings and the second plurality of openings, said flow baffle operative to cause refrigerated air flowing past the flow baffle to reverse flow direction to pass through the second plurality of openings in said generally horizontal panel.
 19. A refrigerated merchandiser as recited in claim 17 wherein said generally vertical panel has a lower portion having a third plurality of openings disposed in and therethrough for passing refrigerated air from said air supply duct into the interior product display space.
 20. A refrigerated merchandiser as recited in claim 17 wherein said generally vertical panel has a lower portion having a third plurality of openings disposed in and therethrough for passing refrigerated from said air supply duct from into the interior space, an upper portion without openings therethrough, and an intermediate portion between the upper and lower portions having a fourth plurality of openings therethrough for passing refrigerated air from said air supply duct into the interior space.
 21. A refrigerated merchandiser as recited in claim 20 wherein said third plurality of openings in the lower portion of said generally vertical panel define a flow a first flow area and said fourth plurality of openings in the intermediate portion of said generally vertical panel define a second flow area, the first flow area being larger than the second flow area.
 22. In a refrigerated merchandiser having a cabinet having an interior space having a product displayed therein and refrigerated by supplying refrigerated air to the interior space, a method for refrigerating the product comprising the steps of: supplying refrigerated air to an upper region of the interior space; directing the refrigerated air supplied to the upper region of the interior space generally downwardly through the product displayed in the interior space; and withdrawing air from a lower region of the interior space; whereby the refrigerated air supplied to the upper region of the interior space flows in a generally vertically downward path through the product displayed in the interior space.
 23. A method as recited in claim 22 wherein the step of directing the refrigerated air supplied to the upper region of the interior space generally downwardly through the product displayed in the interior space comprises the steps of: directing a first portion of the refrigerated air supplied to the upper region of the interior region in a generally downwardly and forwardly direction; and directing a second portion of the refrigerated air supplied to the upper region on the interior region in a generally downwardly and rearwardly direction.
 24. A refrigerated merchandiser having an interior space wherein a product may be displayed in an environment refrigerated by refrigerated air supplied to the interior space, comprising: a cabinet having a top wall, a lower wall having an air return outlet passing therethrough, a rear wall, and side walls bounding the interior space; and a rear panel disposed in the interior space in spaced relationship from and generally parallel to the rear wall of said cabinet and defining a generally vertically extending air supply duct therebetween, said air supply duct having an inlet for receiving the refrigerated air and an outlet at its upper end for passing a first portion of the refrigerated air from said air supply duct into an upper region of the interior space; said air supply duct having a first flow area upstream of the outlet thereto and a second flow area at the outlet thereto, the second flow area being less than the first flow area.
 25. A refrigerated merchandiser as recited in claim 24 further comprising a flow restriction disposed at the outlet of said air supply duct, said flow restriction restricting the second flow area to a flow area less than the first flow area.
 26. A refrigerated merchandiser as recited in claim 24 further comprising a flow baffle disposed at the outlet of said air supply duct, said flow baffle restricting the second flow area to a flow area less than the first flow area.
 27. A refrigerated merchandiser as recited in claim 26 wherein said flow baffle comprises an extension of said rear panel extending obliquely at an upper end of said rear panel toward said rear wall of the cabinet.
 28. A refrigerated merchandiser as recited in claim 24 wherein flow baffles extends obliquely rearwardly at an angle in the range of from about 30 to about 60 degrees.
 29. A refrigerated merchandiser as recited in claim 24 wherein the second flow area is about ¼ to ¾ the area of the first flow area. 